The effect of powder-pack aluminising on the corrosion performance of FeCoGx low entropy alloys

Non-reinforced, 3% and 5% nano graphene reinforced FeCo alloy was produced by powder metallurgy and TIG melting methods, and the coating was made using the pack aluminising method. Scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) and microhardness measurements were used in characterisation processes. Co7Fe3Al10, Co2Al5, FeCoAl, FeAl, Fe2Al5, and Al2O3 phases were detected on the coated sample surfaces. The coating layer thicknesses were obtained between 86 μm and 132 μm with the aluminium. With the coating, it was determined that the surface hardness of the samples increased by more than two times. Better corrosion resistance results were obtained in production with TIG melting compared to powder metallurgy of FeCo alloy. The best corrosion resistance in the FeCoGx alloy, which is coated with pack aluminising, has been determined in production with TIG melting, which has the highest graphene reinforcement (5%) and the highest coating layer thickness.